Method and machine for making shackles



June 12, 1956 F. J. WELSCH 2,749,610

METHOD AND MACHINE FOR MAKING SHACKLES Filed Sept. 20, 1952 2Sheets-Sheet 1 N. 6 INVENTOR.

[%d mq W ATT R/IE Y5 0- FRANKJ. WELSCH June 12, 1956 F. J. WELSCH METHODAND MACHINE FOR MAKING SHACKLES Filed Sept. 20, 1952 2 Sheets-Sheet 2 VIWVIIIIIIAQWVIIIIQMJVI 10 INVENTOR.

FZ ANK J WEL SCH M wZZwg A TTOH/YE v5 United States Patent 2,749,610METHOD AND MACHINE FOR MAKING SHACKLES Frank John Welsch, Campbell,Calif. Application September 20, 1952, Serial No. 310,645 7 Claims. (Cl.29-545) The present invention relates to forging, and pertains moreparticularly to a machine and method for use in the forging of chainshackles.

In naval and marine work, large quantities of shackles are employed foruse on the numerous types of chains used in the securing and hoisting ofvarious equipment and commodities aboard ship. The making of theshackles for securing the ends of such chains has been the subject of aconsiderable amount of development, and in the past several attemptshave been made to improve the usually slow and tedious process ofmanufacturing these shackles.

The present invention contemplates the provision of an improved machinefor the manufacturing of chain shackles.

The invention also provides an improved method for the making of chainshackles.

It is also the purpose of the present invention to provide a machine forthe manufacture of chain shackles whereby successive steps of theirmanufacture can be carried on in a simple and easy manner and with theuse of a minimum amount of power and equipment.

A further object of the invention is to provide a machine for themanufacture of chain shackles which will permit manufacture of theshackles at a minimum cost and with a maximum degree of uniformity.

These and other objects and advantages of the invention will be apparentfrom the following description and the accompanying drawings, wherein:

Fig. 1 is a fragmentary perspective view showing the punch and die zoneof a forging press with punches and dies embodying the present inventionand capable of operating in accordance with the method of the presentinvention, portions of associated parts of the press also being shown.

Fig. 2 is an enlarged perspective view of a shackle made in accordancewith the method of the present invention by mechanism such as that shownin Fig. 1.

Fig. 3 is a perspective view of a shackle pin for use with the shackleshown in Fig. 2.

Fig. 4 is a fragmentary horizontal sectional view taken as on line 4-4of Fig. 7, but showing the dies in shut, or closed position, and theram, with the piercing die mounted therein, advanced.

Fig. 5 is a fragmentary horizontal sectional view taken along line 5-5of Fig. 7.

Fig. 6 is a fragmentary horizontal sectional'view taken along line 6--6of Fig. 7, a portion of the ram, with a forming punch mounted therein,being shown in advanced position in broken lines.

Fig. 7 is a fragmentary vertical sectional view taken on a plane definedby the axes of the three punches shown in Fig. 1. p

' Fig. 8 is a side elevational view of a length of rod used for making ashackle blank.

Fig. 9 is a side elevationalview of the shackle blank formed from therod shown in Fig. 8.

Fig. 10 is a perspective View of the blank shown in Fig. 9 after a-lugforming operation has been completed thereon.

Referring to the drawings, the machine A shown in Fig. 1, for the makingof shackles B (Fig. 2), is a gen-1 erally conventional two stagehorizontalforging press.

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The machine A has a pair of laterally converging die holders 10, 10 witha pair of similar but opposite die blocks 11, 11 mounted thereon. Thedie holders 10, 10 are arranged to move the die blocks 11, 11 intoclosely abutting relationship, and to dwell with the dies held in suchclosed position for a predetermined length of time during each operatingcycle of the machine A.

Forming punches 12, 12 and a piercing punch 13 are mounted on a punchblock 14 which is secured by bolts 15 in a conventional manner to theram 17 of themachine A. During each cycle of operation of the machine A,after the dies 11, 11 have been moved to their closed position, thepunches 12, 12 and 13 will be advanced and then retracted before thedies 11, 11 again are moved to their open position as shown in Fig. 1.

Each die block 11 has a horizontal U-shaped lower die cavity 18 thereinclosely to receive a U-shaped work piece 19 (Fig. 9) therein. A recess20 is provided at the bight portion of each U-shaped lower cavity 18 toprovide clearance for the nose portion of a con-- ventional pair oftongs (not shown) used for handling the blanks 19 when inserting them inthe cavities 18 and removing them therefrom.

Deepened portions 21, 21 are provided one in each leg of the diecavities 18, 18 for forming enlarged lugs 22 and 23 (Fig. 10) on theends of the legs 19a and 19b, respectively, of each work piece 19. Thework piece with the lugs 22 and 23 formed thereon will be referred to asthe shackle blank 26. The deepened cavity portions 21, 21 are ofgenerally semi-circular configuration as shown in Fig. 6.

The forward or right hand ends of the forming punches 12, 12 (Figs. 1, Sand 7) are of a concavity, and the punches are of a length, relative tothe stroke of the ram 17, to complement the curvature of the deepenedportions 21, 21 of the U-shaped die cavitives 18, 18 when the die blocks11, 11 are in their closed position, and the ram 17 is fully advanced asshown in broken lines in Fig. 6.

Thus, upon the advancement of the forming punches into the left handends of the legs of the U-shaped die cavity 18, the material of the legs19a and 19b of the U-shaped blank 19 which extend beyond the deepenedcavity portions 21, 21 is forced back into the deepened cavity portions21, 21. This operation forms lugs 22 and 23 on the ends of the legs 24and 25, respectively, and changes the work piece 19 to the formedshackle blank 26 (Fig. 10).

It will be noted in Fig. 9 that the other leg 1% of the U-shaped blank19 is slightly shorter than the other leg 19b thereof. The respectivelengths of the legs 19a and 19b of the blank 19 are such that the lug 22(Fig. 10) formed on the shorter leg by the forward stroke of the formingpunches 12, 12 will be slightly smaller than the lug 23 formed on thelonger leg 1%. The machine A completes its first cycle of operation byretracting the ram 17, by withdrawing the punches 12, 12 and 13, andthen separating the die blocks 11, 11 to the position thereof shown inFig. 1.

Upper die cavities 28, 28 (Fig. 1) each comprise a pair of horizontalsemi-cylindrical portions 29, 29, one of said cavities extendinglengthwise of each die block 11. Three deepened cavity portions 30, 31and 32 are formed coaxially of each of said cavity portions 29, 29.These cavities 28, 28 are complementary to each other when the dieblocks 11, 11 are in their closed position as shown in Fig. 4. Thedeepened cavity portions 30, 31 and 32 are of a size, and are spacedapart, to receive the lugs 22 and 23 of the formed shackle blank 26, asshown in Fig. 10, when the shackle blank 26 is positioned in either ofthe two broken line positions 2611 or 26b shown in Fig. 7.

The piercing punch 13 is mounted on the block 14 in position to alignaxially with the complementary semieylindrical recesses 29, 29 when thedie blocks 11, 11 are in their closed position, as shown in Fig. 4-. Thepiercing punch 13 has the base or lefthand portion 33 thereof (Figs. 2and 7) of a diameter slightly less than that of the larger shank portion33a of the shackle pin C shown in Fig. 2. This larger diameter portion33 of the piercing punch 13 is of a length to extend beyond the firstenlarged die cavity portion 30 when the ram 17 is fully advanced asshown in Fig. 4. The outer or right hand portion 34 of the piercingpunch 13 is reduced to a diameter slightly less than that of thethreaded end portion 34a of the shackle pin C, and is of a length toextend beyond the central deepened cavity portion 31 when the ram isfully advanced. The intermediate portion 35 of the punch lying betweenthe larger diameter base portion 33 and the smaller diameter outerportion 34 is tapered from one of said diameters to the other. Usualclearances are provided between the piercing punch 13 and the die blocks11, 11.

The operation of the herein disclosed mechanism, and the method employedin the making of the shackles B (Fig. 2) is as follows:

A plurality of straight lengths 37 (Fig. 8) of round bar stock ofsuitable metal are cut off and are bent to form the work piece 19 shownin Fig. 9 by conventional bending dies, not shown. One leg 19a of theU-shaped work piece 19 is slightly shorter than the other leg 19bthereof, as mentioned previously herein. A plurality of the U-shapedwork pieces 19 are heated to a desired forging temperature by aconventional furnace or other heating means, not shown. The heated workpieces 19 then are seized at their bights, one at a time, by an operatorusing conventional tongs. not shown, and are placed in one of the lowerU-shaped cavities 121 in the position indicated by dash-two-dot lines inFig. 7. The recesses 20, 20 at the right hand end (Fig. 7) of thecavities 18, 18 provide clearance for the nose of the tongs when thedies are moved to their closed position as shown in Fig. 6. The machineA then is operated in a usual manner, first to close the die blocks 11,11 to grip the blank 19 there between, and then to advance the ram 17 tomove the forming punches 12, 12 to the position indicated in dashone-dotlines in Fig. 6. This action of the forming punches forces the endportions of the legs 1% and 19b of the blank 19 which extend beyond thedeepened cavity portions 21, 21 back into these deepened cavityportions.

This action by the forming punches 12, 12 forms the lugs 22 and 23 onthe shackle blank 26 (Fig. The operator then, by means of usual tongs,removes the shackle blank 26 thus formed from the lower die cavity 18and places it, still at forging temperature, in the upper die cavity 28in the position indicated by the right hand dash-three-dot line 26a inFig. 7. In this position of the shackle blank 26, the smaller lug 22,which was formed on the shorter leg 19a of the blank 19, will bepositioned in the central recessed portion 31 of the upper cavity 28,and the other or larger lug 23 will be positioned in the right handrecessed cavity portion 32. The machine A then is operated throughanother cycle. During this second cycle of operation, after the dieblocks 11, 11 have been moved to their closed position, the ram 17 isoperated to advance the piercing punch 13 to the position shown in Fig.4, thereby punching a hole of the diameter of the reduced outer or righthand end portion 34 of the piercing punch 13 in the smaller or left handlug 22 of the shackle blank 26.

Upon completion of this second cycle of operation of the machine A, withthe ram 17 retracted to the position thereof shown in Fig. 7 and the dieblocks 11, 11 separated as shown in Fig. l, the shackle blank 26, withits left hand lug 22 pierced, is removed from the right hand pair ofupper die recesses 31 and 32, and is. replaced in the die with thepierced smaller lug 22 in the left hand recess 30 and the larger lug 23in the central recess 31 as shown by the dash-two-dot line 26b in Fig.7. At this stage of operation, a fresh U-shaped blank 19 may be placedat forging temperature in one of the lower U- shaped cavities 18. Thepress then is operated through a third cycle (with respect to the blank26 in the recesses 31 and 32) to close the die blocks 11, 11 and toadvance the ram 17.

As the piercing punch 13 again is advanced to the position shown in Fig.4, with the shackle blank in the left hand position 2611 of Fig. 7, itwill be noted that the tapered intermediate portion 35 and a portion ofthe larger diameter base portion 33 of the piercing punch 13 will beforced through the hole made in the smaller lug 22 by the precedingstroke of the ram 17 when the shackle blank 26 was in the right handposition 2611 of Fig. 7. This action of the tapered punch 13 enlargesthe hole in the smaller lug 22 and expands the surrounding metal of thelug 22 radially outwardly rela tive to the punch axis, thereby causingthe lug 22 to fill the recesses 30, 36. By this action the smaller lug22 is expanded, as shown in the completed shackle B in Fig. 2, to thesame external size as the larger lug 23. During this same third strokeof the ram 17, the piercing punch 13 also punches a hole in the righthand lug 23 of the shackle blank 26, which lug is at that timepositioned in the central die recesses 31, 31.

Each slug, not shown, punched from the lugs 22 and 23 by successivestrokes of the punch 13 is carried beyond its respective lug and intothe opening formed by the channels 29, 29 as the punch 1.3 completeseach punching stroke. These slugs usually drop by gravity out of thechannels 29, 29 when the dies 11, 11 are separated upon the completionof an operative cycle of the press. Should they tend to hang up in thecavities 23, 28 however, they may be easily freed by tapping them withthe tongs or other tool to cause them to drop clear of the dies.

This third cycle of operation of the machine A completes the shackleexcept for a usual final tumbling operation, the reaming of the largerhole 38 (Fig. 2) and the threading of the smaller hole 39 to receive theconventional shackle pin C, all in a usual manner.

In the event that extremely large runs of a particular size of shackleare contemplated, it is possible to expedite the operation somewhat bymaking the lower portion of the die blocks 11, 11 having the U-shapedcavities 18, 18 therein separately, and by performing the initiallugforming operation in a separate press, having separate formingpunches similar to the punches 12, 12. When this latter procedure isfollowed, it is desirable to have the presses located closely adjacenteach other so that blanks may be processed from the work piece heatingmeans to the lug-forming press and thence to the punching or piercingpress without intermediate handling or heating of the work pieces orblanks.

While I have illustrated and described a preferred embodiment of thepresent invention, it will be understood however, that various changesand modifications may be made in the details thereof without departingfrom the spirit and scope of the invention as set forth in the appendedclaims.

Having thus described the invention, What I claim as new and desire toprotect by Letters Patent is defined in the following claims.

I claim:

1. In a forging press having a pair of die blocks movable toward andaway from each other and having a ram movable at right angles to thedirection of die block movement; a plurality of aligned, lug receivingcavities in each die block, the cavities in one die block beingcomplementary to those in the other, said cavities being formed andarranged to receive lugs on a shackle blank in either of two selectedpositions therein, said die blocks having an opening formed therein toextend through a first and a second of the aligned lug receivingcavities, and a piercing punch mounted on the ram to enter said opening,said punch being of a length to project, on an operative movement of theram, through said first and second cavities, the portion of the punchpassing through said second cavity being of a size to punch a hole ofpredetermined size in the lug of a shackle blank therein, and theportion of the punch passing through said first cavity being of a largerdiameter than the portion passing through said second cavity.

2. The method of forming a shackle blank with holes of differentdiameter in the end lugs thereof, which comprises bending a straightlength of bar stock to form a Work piece of U-shape to have one legthereof longer by a predetermined amount than the other leg, forming theend portions of the legs into lugs .to bring the legs to equal length,thereby forming the lug on the longer leg of the work piece of a sizelarger than the lug on the shorter leg, forcing the small end of a punchhaving a smaller diameter punching portion and a larger diameterexpanding portion through the smaller of said lugs to pierce it with ahole axially directed toward the center of the larger lug, moving thework piece closer to the punch and advancing the punch axially throughthe hole in the smaller lug to pass the larger diameter portion of thepunch through the hole formed in the smaller lug to expand said smallerlug and to increase the diameter of the hole therein, the punch beingadvanced a sufficient distance to pass the small end of the punchthrough the larger lug to pierce it.

3. A mechanism for making a shackle blank from a U-shaped work piecehaving laterally opposite lugs of different size formed on the ends ofthe legs thereof, said mechanism comprising; means for holding the lugsin a first predetermined position, a punch having a punching end portionof predetermined diameter and having an expanding portion of largerdiameter spaced rearwardly therefrom, means operable to advance saidpunch along an axial path centrally intersecting the lugs when grippedin said first position to punch a hole in the smaller of said lugs, andmeans for gripping the lugs in a second predetermined position closer tothe punch and with the hole punched in said one lug aligned axially withthe punch, said punch advancing means being again operable axially toadvance the punch along said path with the lugs gripped in their secondadjusted position, thereby passing said punch through the hole punchedin the smaller lug a distance sufficient to pass the enlarged punchportion through said hole thereby enlarging the hole and expanding thesmaller lug, and in the same stroke passing the punching portion of thepunch through the larger lug to punch a hole therein.

4. In a forging press having a pair of die blocks movable between openand closed position, a plurality of aligned, lug receiving cavities ineach die block, said aligned cavities in one die block beingcomplementary to those in the other, the aligned cavities in each dieblock being spaced apart by the distance separating a pair of lugsformed on the legs of a U-shaped work piece, complementary semicircularchannels extending centrally through a first and a second of saidaligned lug receiving cavities, and a piercing and expanding punchmounted to enter the semi-circular channels in a closed position of thedie blocks, said piercing punch being of a length to project through afirst and a second of said aligned cavities, the portion of the punchpassing through said second cavity being of a size to punch a hole ofpredetermined size in the lug of a shackle blank therein, and theportion of the punch passing through said first cavity being of largerdiameter than the punch portion passing through said second cavity, aportion of the punch located between said two punch portions beingtapered to exert an expanding force on a lug in said first cavity inpassing through a pre-punched hole in such latter lug.

5. In a forging press having a pair of die blocks movable between openand closed condition, and having a ram movable at right angles to themovement of the die blocks; each die block having three lug receivingcavities therein aligned in the direction of ram movement and spacedapart to receive, in either of two positions, the lugs of a work piecewith a pair of lugs formed thereon, each die block having a straightpunch receiving cavity extending centrally of said lug receivingcavities in the direction of ram movement, the straight cavity portionextending through the first lug receiving cavity toward the ram being oflarger diameter than the portion thereof extending through other lugreceiving cavities, and a piercing punch mounted on the ram to entersaid straight cavity during an operative stroke of the ram to passwithin the straight cavity through two of the three lug receivingcavities, the portion of the punch passing through the second lugreceiving cavity from the ram being of smaller diameter than the punchportion passing through said first lug receiving cavity, thereby toprepunch a hole in a first lug positioned in the second of said two lugreceiving cavities in one position of the work piece, and to passthrough and enlarge the prepunched hole in said first lug, and to puncha hole in the other of said lugs in a second position of said work piecein said lug receiving cavities.

6. In a forging press having die holders movable toward and away fromeach other, and having a ram movable at right angles to the direction ofdie holder movement; a pair of die blocks mounted on the die holders tomove from open to shut position, each die block having three centrallyaligned lug receiving cavities therein, said cavities beingcomplementary to each other in a shut condition of the die blocks, saidcavities being spaced apart to receive, in either a first or a secondpredetermined position, the lugs of a U-shaped shackle blank having lugson the legs thereof, said die blocks having a punch receiving openingtherein extending, in the shut condition of the die blocks, centrallythrough a first and a second of said lug receiving cavities, and apiercing punch mounted to enter said punch receiving opening during anoperative stroke of the ram to pass in sequence through said first andsecond lug receiving cavities, thereby, in a first of said predeterminedpositions of the work piece, to punch a hole in a first lug positionedin the second of said lug receiving cavities, and, in a secondpredetermined position of the work piece, with the first lug positionedin the first of said lug receiving cavities, to pass through the holepunched in the first lug in said first predetermined position of thework piece, and to punch a hole in the second of said lugs positioned inthe second of said lug receiving cavities.

7. An arrangement according to claim 6 wherein the punch is enlarged ata point between the first and second lug receiving cavities in anadvanced position of the punch to expand said first lug in passingthrough the hole therein with the work piece positioned in said secondpredetermined position thereof.

References Cited in the file of this patent UNITED STATES PATENTS140,422 Krementz July 1, 1873 228,907 Lanz June 15, 1880 350,859Anderson Oct. 12, 1886 399,903 Kennedy Mar. 19, 1889 535,301 Smith Mar.5, 1895 1,070,121 Ecseghy Aug. 12, 1913 1,250,411 Amiot Dec. 18, 19171,313,949 Mountford Aug. 26, 1919 1,756,376 Moore Apr. 29, 19301,984,350 Halsey Dec. 11, 1934 1,997,871 Miller Apr. 16, 1935 2,621,344Friedman Dec. 16, 1952

